Transcriptomics of drougth stress in L. japonicus under normal air conditions
ABSTRACT: L. japonicus (Regel) Larsen cv, Gifu were initially obtained from Prof. Jens Stougaard (University Aarhus, Denmark) and then self-propagated at the University of Seville. Seeds were scarified and surface-sterilized, germinated in 1% agar Petri dishes, and transferred to pots using a 1:1 (v/v) mixture of vermiculite and sand as solid support. Five seedlings were planted in each pot and grown during 35 days in a growth chamber under 16/8 hours day/night, 20/18ï¿½C, with a photosynthetic photon flux density of 250 ï¿½mol/m2ï¿½s and a constant humidity of 70%. Plants were watered with Hornum nutrient solution. Drought was applied withholding irrigation for the reported period of time and sample plants or leaves were harvested for further analysis.
Project description:L. japonicus (Regel) Larsen cv, Gifu were initially obtained from Prof. Jens Stougaard <br>(University Aarhus, Denmark) and then self-propagated at the University of Seville.<br> Ljgln2-2 mutant was isolated from photorespiratory mutant screening as described <br>previously (Orea et al., 2002; Mï¿½rquez et al., 2005; Betti et al., 2006). <br>The mutant progeny of two consecutive back-crosses with WT was used<br> for the present work. WT and mutant seeds were scarified and surface-sterilized,<br> germinated in 1% agar Petri dishes, and transferred to pots using a 1:1 (v/v) mixture<br> of vermiculite and sand as solid support. <br>Five seedlings were planted in each pot and grown <br>during 35 days in a growth chamber under 16/8 hours<br> day/night, 20/18ï¿½C, with a photosynthetic photon flux <br>density of 250 ï¿½mol/m2ï¿½s and a constant humidity of 70%.<br> CO2 was automatically injected to a final concentration of 0.7% (v/v),<br> to allow for normal growth of Ljgln2-2 mutant in a photorespiration <br>suppressed atmosphere. Plants were watered with Hornum nutrient solution <br>(Handberg & Stougaard, 1992).<br> Drought was applied withholding irrigation for the reported period <br>of time and sample plants or leaves were harvested for further analysis.
Project description:Many plant researchers have applied genomic tools to model species to identify abiotic stress responsive genes that might be useful for improving stress tolerance in crops. However, it is unclear whether this translational approach will be successful given the complexity of abiotic stress tolerance. We carried out a functional genomic (ionomic, transcriptomic and metabolomic) comparison of three model and three forage species of the genus Lotus with varying tolerance to salinity. Transcriptome analysis showed that about 60 % of expressed genes were responsive to salt treatment in one or more of the six species tested, but less than 1 % was responsive in all genotypes. Therefore, genotype-specific responses overshadowed conserved transcriptional responses to salinity and represent an impediment to translational genomics. Fortunately, 'triangulation' from multiple species enabled the identification of a core set of conserved and tolerant-specific responses that could provide durable tolerance across genotypes.
Project description:Model legume Lotus japonicus was subjected to non-lethal long-term salinity and profiled at the transcriptomic level. Three independent experiments were performed, testing two experimental designs: a traditional gradual acclimation following a step-wise increase of salt concentration and an initial acclimation approach (ia).
Project description:Transcriptomic profiling was carried out for leaves of Lotus japonicus plants grown with different mineral nitrogen sources (NO3-, NH4+ or NH4NO3) or under conditions of biological nitrogen fixation (Nod). Nodulated plants were inoculated with Mesorhizobium loti and watered with nitrogen-free “Hornum” medium supplemented with 3 mM KCl. Plants under different nitrogen nutritions were watered with “Hornum” nutrient solution containing 10 mM KNO3 (NO3- plants) or with 10 mM NH4Cl supplemented with 3 mM KCl (NH4+ plants) or with 5 mM NH4NO3 supplemented with 3 mM KNO3 (NH4NO3 plants). After all the plants reached the size of 7 trifoils, leaf tissue was harvested. Every harvest involved at least three independent biological replicates for each treatment.
Project description:Wildtype and mutant plants lacking the plastidic isoform of glutamine synthetase were grown under CO2-enriched atmosphere and then transferred to low CO2 conditions. Transcriptomic profiling was carried out for plants under CO2-enriched atmosphere and plants after 2 days of transfer to low CO2 conditions.
Project description:Roswell Park Human 19K Array CGH<br><br>the format of the data is:<br> <br>Reporter Identifier<br>Band<br>Count - number of replicate spots the data represents (some spots are excluded in image analysis, usually because they are too dim to be reliable)<br>chr - Chromosome<br>Start - Start location in base pairs<br>Stop - Stop Location in Base pairs<br>Center - Center in base pairs<br>g_loc - graphing location this is the location of the center in base pairs if the chromosomes were laid end to end<br>Log2 ratio - log2 ratio (test/control)<br>Ratio - linear version of the ratio above <br>A - Measure of brightness A=(log2 cy3 + log2 cy5)/2 <br>Flag - Used to color code spots<br> 3 - red probably mismapped<br> 4 - green potentially polymorphic<br> 5 - light blue Shows a high degree of duplication with other area in the genome (see UCSC genome browser) <br>reference - Reference for why the clone was flagged <br>Pub Med link - Pub Med ID for why clone was flagged
Project description:Fission yeast cells belong to one of two specialized cell types, M or P. Specific environmental conditions trigger sexual differentiation, which leads to an internal program starting with pheromone signalling between M and P cells, followed by mating, meiosis and sporulation. The initial steps of this process are controlled by Ste11p, a master transcriptional regulator that activates the expression of cell type-specific genes (only expressed in either M or P cells) as well as genes expressed in both M and P cells. <br><br> Pheromone signalling is activated by Ste11p-dependent transcription, and in turn enhances some of this transcription in a positive feedback. To obtain a genome-wide view of Ste11p target genes, their cell-type specificity, and their dependence on pheromone, we used DNA microarrays along with different genetic and environmental manipulations of fission yeast cells.We directly compared the transcriptome of homothallic wild-type cells (h90 fus1) with that of ste11 delta mutants under conditions that induce sexual differentiation. To allow for indirect effects of the ste11 delta mutation, we took advantage of the fact that ectopic expression of ste11 can drive cells into sexual differentiation and therefore is expected to cause the expression of Ste11p targets. We thus defined Ste11p targets as those genes whose expression was significantly reduced in a ste11 delta mutant and significantly increased when ste11 is overexpressed in vegetative cells.<br> <br> This study looked at the effect of deletion or overexpression of ste11, and changes in gene expression after nitrogen starvation of h plus, h minus, h90fus1 and h90ste11 cells.
Project description:Hodgkin lymphoma derived cell lines (from the Deutsche Sammlung von Mikroorganismen und Zellkulturen) were cultured in RPMI 1640 medium supplemented with <br><br>20% (HDML-2) or 10% (HD-MY-Z) heat inactivated fetal calf serum. Cytoplasmic RNA was extracted according to "Cytoplasmic_RNA_CRG" protocol available at Arrayexpress